Effect of hemicellulolytic enzymes to improve sugarcane bagasse saccharification and xylooligosaccharides production

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Enzymatic hydrolysis of lignocellulosic biomass is limited by economic considerations arising from enzyme production costs and specific activities. The effect of six hemicellulases on raw sugarcane bagasse and two types of pretreated sugarcane bagasse was investigated using experimental designs. Our strategy was successful for developing more efficient and less expensive enzymatic mixture, and also revealed that hemicellulase mixtures with multiple activities could be less effective than expected. In this study, only two hemicelulases, the endo-1,4-xylanases (GH11) from Penicillium funiculosum (XynC11/CAC15487) and the feruloyl esterase (CE1) from Clostridium thermocellum (CtFAEIATCC27405), effectively broke down hemicellulose from pretreated sugarcane bagasse (up to 65%), along with the production of xylooligosaccharides (XOS). Our results also demonstrated that GH11 and CE1 can improve biomass saccharification by cellulases. Treatment with these two enzymes followed by a commercial cellulase cocktail (Accellerase (R) 1500) increased saccharifi cation of pretreated lignocellulose by 24%. Collectively, our data contributes to the rational design of more efficient and less expensive enzyme mixtures, targeting the viable production of bioethanol and other biorefinery products. (C) 2016 Elsevier B.V. All rights reserved.Enzymatic hydrolysis of lignocellulosic biomass is limited by economic considerations arising from enzyme production costs and specific activities. The effect of six hemicellulases on raw sugarcane bagasse and two types of pretreated sugarcane bagasse was1313646FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNQP - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)2012/18859-52012/20549-4SEM INFORMAÇÃOWe are grateful to FAPESP (The State of São Paulo Research Foundation) for the pos-doctoral scholarship and financial support (2012/18859-5 to RG2012/20549-4 to ARLD, respectively).This work was also financially supported by the CNPq (National Counci

Assembling a xylanase-lichenase chimera through all-atom molecular dynamics simulations

Multifunctional enzyme engineering can improve enzyme cocktails for emerging biofuel technology. Molecular dynamics through structure-based models (SB) is an effective tool for assessing the tridimensional arrangement of chimeric enzymes as well as for inferring the functional practicability before experimental validation. This study describes the computational design of a bifunctional xylanase-lichenase chimera (XylLich) using the xynA and bglS genes from Bacillus subtilis. In silico analysis of the average solvent accessible surface area (SAS) and the root mean square fluctuation (RMSF) predicted a fully functional chimera, with minor fluctuations and variations along the polypeptide chains. Afterwards, the chimeric enzyme was built by fusing the xynA and bglS genes. XylLich was evaluated through small-angle X-ray scattering (SAXS) experiments, resulting in scattering curves with a very accurate fit to the theoretical protein model. The chimera preserved the biochemical characteristics of the parental enzymes, with the exception of a slight variation in the temperature of operation and the catalytic efficiency (k cat/Km). The absence of substantial shifts in the catalytic mode of operation was also verified. Furthermore, the production of chimeric enzymes could be more profitable than producing a single enzyme separately, based on comparing the recombinant protein production yield and the hydrolytic activity achieved for XylLich with that of the parental enzymes. © 2013 Elsevier B.V. All rights reserved